summaryrefslogtreecommitdiffstats
path: root/drivers/clocksource
diff options
context:
space:
mode:
authorRichard Cochran <rcochran@linutronix.de>2016-07-13 17:17:05 +0000
committerIngo Molnar <mingo@kernel.org>2016-07-15 10:41:44 +0200
commitd11b3a60fcc8c6e44dd370f1cf2738eb5bec7353 (patch)
tree66875201bd823b31ffcb23986e864b06905d450f /drivers/clocksource
parentb8a12296ac812f829bd9392346b01b1872d8118b (diff)
downloadop-kernel-dev-d11b3a60fcc8c6e44dd370f1cf2738eb5bec7353.zip
op-kernel-dev-d11b3a60fcc8c6e44dd370f1cf2738eb5bec7353.tar.gz
clocksource/exynos_mct: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Richard Cochran <rcochran@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com> Cc: Kukjin Kim <kgene@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-samsung-soc@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153338.147940411@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/exynos_mct.c46
1 files changed, 12 insertions, 34 deletions
diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
index 0d18dd4b..41840d0 100644
--- a/drivers/clocksource/exynos_mct.c
+++ b/drivers/clocksource/exynos_mct.c
@@ -443,10 +443,11 @@ static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static int exynos4_local_timer_setup(struct mct_clock_event_device *mevt)
+static int exynos4_mct_starting_cpu(unsigned int cpu)
{
+ struct mct_clock_event_device *mevt =
+ per_cpu_ptr(&percpu_mct_tick, cpu);
struct clock_event_device *evt = &mevt->evt;
- unsigned int cpu = smp_processor_id();
mevt->base = EXYNOS4_MCT_L_BASE(cpu);
snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);
@@ -480,8 +481,10 @@ static int exynos4_local_timer_setup(struct mct_clock_event_device *mevt)
return 0;
}
-static void exynos4_local_timer_stop(struct mct_clock_event_device *mevt)
+static int exynos4_mct_dying_cpu(unsigned int cpu)
{
+ struct mct_clock_event_device *mevt =
+ per_cpu_ptr(&percpu_mct_tick, cpu);
struct clock_event_device *evt = &mevt->evt;
evt->set_state_shutdown(evt);
@@ -491,39 +494,12 @@ static void exynos4_local_timer_stop(struct mct_clock_event_device *mevt)
} else {
disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
}
+ return 0;
}
-static int exynos4_mct_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- struct mct_clock_event_device *mevt;
-
- /*
- * Grab cpu pointer in each case to avoid spurious
- * preemptible warnings
- */
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
- mevt = this_cpu_ptr(&percpu_mct_tick);
- exynos4_local_timer_setup(mevt);
- break;
- case CPU_DYING:
- mevt = this_cpu_ptr(&percpu_mct_tick);
- exynos4_local_timer_stop(mevt);
- break;
- }
-
- return NOTIFY_OK;
-}
-
-static struct notifier_block exynos4_mct_cpu_nb = {
- .notifier_call = exynos4_mct_cpu_notify,
-};
-
static int __init exynos4_timer_resources(struct device_node *np, void __iomem *base)
{
int err, cpu;
- struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
struct clk *mct_clk, *tick_clk;
tick_clk = np ? of_clk_get_by_name(np, "fin_pll") :
@@ -570,12 +546,14 @@ static int __init exynos4_timer_resources(struct device_node *np, void __iomem *
}
}
- err = register_cpu_notifier(&exynos4_mct_cpu_nb);
+ /* Install hotplug callbacks which configure the timer on this CPU */
+ err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
+ "AP_EXYNOS4_MCT_TIMER_STARTING",
+ exynos4_mct_starting_cpu,
+ exynos4_mct_dying_cpu);
if (err)
goto out_irq;
- /* Immediately configure the timer on the boot CPU */
- exynos4_local_timer_setup(mevt);
return 0;
out_irq:
OpenPOWER on IntegriCloud